The Mac version of Jaksta Media Recorder is able to capture HTML5 streams (in general). However, the streaming protocols used are generally site-specific and are not universal.
In the case of jasmin.com, Jaksta is unable to capture those particular HTML5 streams and it would require a fix to be developed specifically for it.
It is not the result of an inherent problem or inability to capture HTML5 streams.
We are aware of this problem and it is currently on our development list, but I can give no ETA on when a fix might be ready.
From Liam @ 17 Jan 2019 12:01